Sierra Leone's presidential and parliamentary polls were free, fair and credible, election observers have said.
The vote was seen as a test of transition to democratic rule
They said the ballot went smoothly and the presence of police gave confidence to voters.
Presidential candidates need 55% of the vote in order to avoid a run-off, which correspondents say is quite likely.
The election is only the second since Sierra Leone emerged in 2001 from a decade-long civil war, during which an estimated 50,000 people were killed.
The previous poll in 2002 was organised by the United Nations, which still had peacekeepers on the ground.
This time, Sierra Leoneans were in charge.
The BBC's Will Ross in Sierra Leone says a run-off next month is a distinct possibility, as three candidates enjoy considerable support.
These are: Solomon Berewa, vice-president of the governing Sierra Leone People's Party; Ernest Bai Koroma, of the All People's Congress and a new political party led by former minister Charles Margai.
Our correspondent says the collation of results is continuing at a slow pace and it will be several days before the official results are out.
The head of the national electoral commission, Christiana Thorpe, told the BBC that the election had proceeded very smoothly.
The EU's chief election observer, Marie-Anne Isler Beguin, said she was satisfied with how the election was conducted.
"Of course we have a good view now, a good picture of what happened and we at this moment can be satisfied with the global participation and the global organisation."
SIERRA LEONE KEY FACTS
1787: Set up as a freed slaves' settlement which became a British colony
1991:10-year civil war began
50,000 people killed in the conflict
Thousands more had limbs chopped off
2002: Post-war elections organised by United Nations
2005: 17,000 UN peacekeepers left
This poll run bynew electoral commission
566 parliamentary candidates
112 parliamentary seats
Seven presidential contenders
- APC's Ernest Bai Koroma
- PMDC's Charles Margai
- SLPP's Solomon Berewa
The ballots are being counted in public - in full view of the party agents - in the country's 6,000 polling stations.
Correspondents say the large turnout was a sign of the population's determination to see Sierra Leone turn its back on years of instability and a civil war.
There had been tension in the run-up to the elections and some feared violence but the police reported no major incidents.
Seven presidential candidates are vying to replace Ahmad Tejan Kabbah, who is stepping down after serving the maximum two terms.
More than 500 candidates are vying for just over 100 parliamentary seats.
About 2.6 million of the country's five million people were registered to vote. Final results are expected within 12 days.